Pneumatic clamp



Oct. 13, 1931. v H. H. PAYZANT 1,827,258 PNEUMATIG CLAMP Filed May s. 19249 28 33M W d? l n ko/(uuid Patented Oct. 13, 1931 'UNITED STATES PATENT OFFICE HENRY H. PAYZANT, F EVERETT, WASHINGTON, ASSIGNOR T0 WEYERHAEUSER TIMBER COMPANY, 0F TACOMA, WASHINGTON, A CORPORATION 0F WASHINGTON IPNEUMATIC CLAMP Application 111e@ May 8, 1929. Serial No. 361,419.

This invention relates to a pneumatic clamp particularly, although not exclusively, adapted for use in securing lumber in bundles such as those described inmy copending ap- 54 plication for patent on a Lumber package, l filed May 16th, 1927, Serial No. 191,602.

It is my object to provide a. readily portable clamp of strong and simple construction adapted to be quickly secured in operatlve K relation to the work and` requiring a mini- 15, tion and claims.

line 4--4 of Fig. 2.

In the accompanying drawings which illustrate the best form of my device at present known to me Figure 1 is a perspective view of the clamp in Yplace on a package of lumber; Fig. 2 is a central longitudinal section through the clamp and lumber package; Fig. 3 is a vertical section through the cylinder and jaws taken at right angles to the section shown in Fig. 2, and Fig. 4 is an enlarged section through the air valve taken on the As illustrated, my device has an air cylinder 5 which is supplied near its normally upper end with air from a flexible conduit 6. Rigidly connected to the normally lower end of the cylinder 5 is a frame 7 having members projecting at opposite sides of the cylinder and having secured to the outer ends of said members, a pair of rods 8. A plate 9 formed with a reinforcing flange 10 extends between the rods 8 in perpendicular relation thereto and to the axis of the cylinder 5. This plate 9 constitutes a stationary jaw of the clamp and has a cushion 11, preferably of sponge rubber, secured to its operating face. Extending in parallel relation to the plate 9 is a plate 12, constituting the movable jaw of the clamp, and provided with a cushion 13, like the cushion 11, for engagement with the object to be held. The plate 12 is perforated at its ends to slidably receive the rods 8 and a piston rod 14 operatively connects the central part of the plate 12 with a piston 15 in the. cylinder 5. Flanges 16 lgive rigidity to the plate 12. A stop plate 17 projects downward and at one side of the plate 12, being rigidly fixed thereto for engagement with the end of a bundle of lumber as hereinafter described.` Coiled springs 18 about the rods 8 are confined between the plates 9 and 12 to urge said plates apart.

To control the admission of air to the cylinder 5 a valve 19 is mounted in a transverse bore in a valve casing 20. Extending through the casing 2O and communicating respectively at opposite ends with the flexible conduit 6 and cylinder 5 is an air passage 21. An exhaust port 22 extends at right angles to the passage 21 in the casing 2O to communicate with a passage 23 in the valve when the same is depressed. This passage 23 is arranged to connect the cylinder 5 with the exhaust port 22 when the valve is depressed. An opening 24 in the valve 19 normally establishes communication between the air conduit 6 and cylinder 5, the valve being normally held in raised position by a spring 25 confined between a valve head 26 and the casing 20. On the lower end of the valve 19 a flange. 27 affords a stop for upward moveand passes freely through a slot in the flange 27 to ali'ord a guide and stop for limiting downward movement of the valve. A handle 29 projects at one side of the cylinder 5, with the flexible conduit 6 secured to `one end and with the valve casing 20 located at the junction of the handle and cylinder so that the valve 19 may be actuated by the thumb of the operator.

My improved clamp is illustrated in use on a plurality of boards 30 which are to be secured together by attaching a flexible end cap 31 of fibre board or the like thereto. Adhesive tape 32 is applied over the ends of the cap 31 and to the adjacent surfaces of the boards 30. When applied in moi-st condition such tape must b e held in place for a short period of time under pressure to cause it to securely adhere to the cap and boards. To secure such packages with my improved clamp, assuming-that air is supplied undery suitable pressure to the conduit 6, the operator grasps the handle 29 and depresses the valve head 26 against the actlon of the spring ,Y ment and a pin 28 is fixed in the valve casing I 25. This cuts ol the supply of air from the hose 6 to the cylinder 5 and connects the cylinder, through the passage 23, with the exhaust'port 22. The springs 18 now raise the plate 12 so that the clamp is, open, ready to receive the package. While in this open position the clamp may be quickly applied to the end cap 31 with the stop plate 17 engaging the end of the bundle, as indicated in Figs. 1 and 2, and then the valve 19 is released to bring the passage 24 into communication with the cylinder 5 and air supply. The piston 15 is thus driven downward and closes the clamp upon the object to be held. By providing the cushions 11 and 13 on the clamping jaws they are caused to conform to the object to be held and to distribute the pressure irrespective of whether or not plane surfaces are presented to the jaws. When the clamp has remained in place for the desired or necessary period of time it may be quickly withdrawn after merely depres-sing the valve head 26 as above described.

It will now be understood that my device is characterized by its simplicity and the ease with which it may be quickly attached and detached from the objects to be held. Obviously it may be used to advantage for holding objects other than bundles of lumber and may be modified without departing from the spirit of the invention.

Having described my invention what l claim is new and desire to protect by Letters Patent is 1. A portable pneumatic clamp comprising an air cylinder, frame members projecting laterall from the bottom of said cylinder, a pair of rods depending in spaced, parallel relation from said frame members, a stationary clamping jaw rigidly secured to the lower ends oit' said rods, a movable clamping jaw slidable upon said rod-s, means normally urging said jaws apart, a piston in said cylinder operatively connected to said movable jaw, a handle projecting laterally Jfrom the upper end of said cylinder, said handle having a pasage therethrough for the admission of air to'said cylinder and a valve near the junction of said handle and cylinder for controlling the operation of said piston in said cylinder.

2. A portable pneumatic clamp comprising an air cylinder, frame members projecting laterally from said cylinder, a pair of rods extending in spaced, parallel relation to each other from said frame members, a clamping jaw rigidly secured to said rods, a second clamping jaw slidable upon said rods, a piston in'said cylinder operatively connected to one of said jaws to actuate the same toward the other jaw, a handle connected to said cylinder and a valve near the junction of said handle and cylinder for controlling the operation of said piston in said cylinder.

3. A portable pneumatic clamp compris.- ing an air c linder, a pair of rods connected to said cyllnder and extending in spaced,

arallel relation to each other, a clamping jaw rigidly secured to said rods, a second clamping jaw slidable along said rods, a piston in said cylinder operatively connected to one of said jaws to actuate the same, a handle connected to said cylinder and a valve near the junction of said handle and cylinder for controlling the operation of said piston in said cylinder.

1n testimony whereof, I have hereunto signed my name to this specification.

HENRY H. PAYZANT.

liu 

